SmogRank / World / France / Brittany / January 2024

Most unhealthy days in Brittany, France, January 2024

5 cities in Brittany, France ranked by their share of unhealthy days over the 31 days. The most unhealthy days: Rennes, France, 1 of 29 measured days. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Rennes 3% 3%0
Every city in Brittany, France ranked for January 2024, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Rennes
    1 of 29
  2. 2Lorient
    0 of 29
  3. 3Vannes
    0 of 29
  4. 4Brest
    0 of 29
  5. 5Saint-Brieuc
    0 of 28
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

All cities in the world, January 2024 · All cities in France, January 2024 · Brittany now

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SmogRank, most polluted cities in Brittany, France, by unhealthy days, PM2.5, January 2024, smogrank.com/fr/region/brittany/history/2024-01?by=days (accessed 7 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.